Suspension Issue?

[bama5er]

I have a 2013 Sierra 38' fifth wheel. I have lost 3 tires due to complete tread separation in 4 years. I thought originally that I had a load rating (E) tire problem. However, after replacing all 5 tires with a F load rated tire I looked closer at the suspension. It seems I only have about an inch clearance from the top of the tire to the RV chassis. This seems very close. I have ALKO axles with Lippert Equi-Flex. My dealer says this is normal for my suspension. The issue is there is evidence (hole) where the tires have hit the bottom of the chassis. I would say this means that 1 inch is not enough clearance. If the tire running at 60-65 MPH hits a stationary object (RV chassis) that would cause the tread separation and a rough ride.

Question: Is there a standard minimum clearance for this?

[bama5er]

All tires show where they have hit the chassis. The right side is the worst and the side that the tires were on when they blew. That's way I'm thinking a suspension issue.

[newman_fulltime]

if clerance was the issue seems like all 4 tires would be hitting.

i have seen one tire hit if it goes over a bump or curb maybe in a turn